1. Field of the Invention
The present invention relates to an image forming apparatus, especially to an image forming apparatus including a scanner device and a plotter device, a power supplying method for this image forming apparatus and a recording medium for this image forming apparatus.
2. Description of the Related Art
An image forming apparatus called Multifunction Peripheral (MFP) or digital complex machine includes several functional groups such as a scanner device and an image forming unit. Then, an electric power control unit may be provided to suppress power consumption by turning on or off power supplies to various portions. The power control unit may turn off a power supplied to the scanner device when a scanner device is not used for a long time as disclosed in Patent Document 1. Patent Document 1 discloses an image forming apparatus for supplying power to the scanner device and an image writing unit only when it is necessary to read an original document or write an image for the purpose of reducing the power consumption.
One type of image forming apparatus may cause the following problems. In order to read images with high image quality, it is necessary for the scanner device to be provided with an initial setting of setting information for reading images at the next power supply after the power supply is once stopped.
In order to reduce the power consumption, the image forming apparatus relatively frequently turns on or off the power supply to the scanner device. Therefore, the initial setting is repeated every turning on or off. Although it does not require a long time for the initial setting, a user may feel frustration if there occur frequent waiting times. Availability of the image forming apparatus is degraded if there occur frequent waiting times for the initial setting.    Patent Document 1: Japanese Laid-Open Patent Application No. 2006-217075.